The Irish outscored France - reduced to 14 after Paul Willemse was red carded in the 32nd minute - five tries to two to consign the home side to their heaviest defeat since Fabien Galthie took over as head coach in 2019.
“We’d take any type of win, on a Friday night in Marseille to kick off the Six Nations,” said Ireland coach Andy Farrell, praising his team’s composure.
“The more the game went on the more you saw the performance building.
“It wasn’t all singing, all dancing. But we were pretty ruthless when we needed to be.”
Lock Tadhg Beirne was outstanding, as was his rookie partner Joe McCarthy, named man of the match.
Meanwhile, Scotland overcame a stunning fightback by Wales to end their 22-year wait for a win in Cardiff with a 27-26 victory yesterday.
The visitors were 27-0 up early in the second half only for the home side to score 26 unanswered points of their own.
Their nail-biting win meant Scotland ended a run of 11 straight defeats in the Welsh capital, a sequence including nine Six Nations losses.
Also yesterday, England managed a hard-fought 27-24 win over Italy in Rome, ending a long-standing opening day hoodoo while failing to convince against their spirited hosts.
Elliot Daly and Alex Mitchell scored England’s two tries with George Ford kicking the rest of the points for Steve Borthwick’s men, who claimed their first round one win since 2019.
England were trailing Italy by nine points mid-way through the first half after superb scores by Alessandro Garbisi and Tommaso Allan.
But Gonzalo Quesada’s Italy couldn’t pull off their first ever win over England on the head coach’s debut in the Azzurri dugout.
It was a promising display from the Italians although the result means they have won just one Six Nations match of their last 43 and have not enjoyed victory at home since 2013.